1. Field
This document relates to an organic light emitting display device and a method of manufacturing the same.
2. Related Art
An organic light emitting element used in an organic light emitting display device was a self emissive element including an emission layer disposed between two electrodes formed on a substrate.
The organic light emitting display device is classified into a top-emission type, a bottom-emission type, and a dual-emission type according to a light emission direction. The organic light emitting display device is also classified into a passive matrix type and an active matrix type according to a driving method.
The organic light emitting display device selects one from a plurality of subpixels arranged in matrix and controls the selected pixel to emit light by applying a scan signal, a data signal, and power to the plurality of subpixels arranged in matrix, thereby displaying images.
Each of the subpixels includes a transistor on a substrate and an organic light emitting diode disposed on the transistor. The organic light emitting diode is classified into a normal type organic light emitting diode and an inverted type organic light emitting diode. In the normal type organic light emitting diode, an anode, an organic light emitting layer, and a cathode are sequentially are formed on a transistor. In the inverted type organic light emitting diode, a cathode, an organic light emitting layer, and an anode are sequentially formed on a transistor.
An organic light emitting display device according to the related art includes the inverted type organic light emitting diode. Such an organic light emitting display device has a problem that reliability and life-span of elements deteriorates because an interface of a cathode is oxidized when an electrode of the cathode is deposited. The organic light emitting display device according to the related art also has another problem that electron injection efficiency decreases due to the oxidation of the cathode. Therefore, it needed to be improved.